[Lab1] 312551098

[EusdenLin]

Description

Add test cases in main_test.js, validated with validate.sh.

• A clear title (name your pr "[LAB{lab_number}] {your_student_id}")
• A meaningful message for PR, as well as its commits
• From your specific branch (not main or other's branch) merging to your branch
• Excluding any irrelevant files, such as binaries, text files, or dot files
• Passing tests/CI

[TaiYou-TW]

Remember to follow PR title's rule next time.